VLAN, TRUNKING, VTP

Vlan trunking

-Vlan divides the broadcast domain
-In New switch, Default Vlan = Native Vlan = Vlan 1
-Native Vlan can be changed from Vlan 1 to Vlan10, 20 etc.
-Vlan 1 cannot be deleted even after entering command
-Vlan 1 carries critical traffic like CDP, VTP etc.
-Access port carries traffic of only one vlan
-Trunk port carries traffic of more than one vlan
-Voice vlan can carry traffic of two vlan’s
-Layer 3 vlan required for Inter-Vlan communication
-On Router, For Inter-Vlan comunication, “Router on Stick” is implemented
-On Switches, For Inter-Vlan comunication,”Layer 3 vlan or SVI” is implemented
-To allow end to end communication, we need to allow Vlan on all the trunk ports in between
-Vlan can be created on Router, Switch, Firewall etc.
-Trunking is the process to enable multiple vlan’s traffic between different switches
-Conditions -Connected Port should be trunk, Encapsulation should match, Allowed Vlans on trunk port should be same

VTP key points

-VTP is Virtual Trunking Protocol, configured to manage Vlan’s
-VTP different versions -V1, V2, V3
-In VTP, different switch roles are Server, Client, Transparent, Off Mode
-Default mode of switch is Server mode
-Recommended to add new switch in Client Mode with Revision number=0
-Revision number can be made zero, if VTP domain name is changes to some bogus name
-Revision number can be made zero, if VTP mode is changes to Transparent mode
-Latest Revision number means Latest Vlan configuration
-Server Mode, we can create, modify & delete vlans
-Client Mode, When client gets update, switch will update itself & passes update further
-Client Mode, We cannot do vlan related changes on client mode, switch will give error message
-Transparent Mode, When Transparent gets update, switch will not update itself & passes update further
-Transparent Mode, Changes performed on the Transparent will not be replicated to other switches
-Off Mode, When switch in Off mode gets update, switch will not update itself and do not pass further

VTP -Different versions

V1,V2 : Support upto Vlan number 1001, V3: Support upto Vlan number 4095
V1,V2 : Cannot transfer details of Private Vlans, V3 : Can transfer details of Private vlan as well
V1,V2 : Cannot carry MSTP region information, V3 : Can carry MSTP region information
V1,V2 : There is no option to make multiple Servers as Primary & secondary,
V3 : We can make Primary server out of multiple Server modes available